Fuel cell stacks are formed from plate-like components and are stacked in repetitious fashion, one atop another. The central plate in each fuel cell in the stack is the electrode plate, which itself is a lamination of several constituent parts. The electrode plate has a first outer cathode or oxygen side part, a second outer electrolyte reservoir part with an adjacent anode or hydrogen side part, and a central matrix part sandwiched between the cathode and anode parts. The electrolyte reservoir part has several holes for hydrogen access to the anode part. The matrix is saturated with an electrolyte liquid. The electrolyte reservoir part, anode, matrix and cathode are bounded by and held together by a fiberglass frame part which includes gas manifold components that form the several manifolds needed for operation of the fuel cell. The electrode plate is itself sandwiched between two gas distribution plates, one of which provides a flow path for oxygen over the cathode, and the other of which provides a flow path for hydrogen over the anode. Each of the gas distribution plates also includes the several manifold components which conform with the aforesaid electrode plate manifold components. The outer periphery of the gas distribution plates abuts the fiberglass frame of the electrode plate, and all of the plates in the stack are tightly clamped together to seal the manifolds and the inner portions of the stack for proper operation. There are a plurality of grooves formed in each of the oxygen distribution plates which extend between each oxygen manifold part and the central oxygen flow path part of the plate. These grooves conduct high purity oxygen from the manifolds to the central flow path for distribution over the cathode. The open sides of the oxygen conducting grooves or ports is closed off by the adjacent clamped fiberglass frame portion of the electrode plate. The areas of the cathode immediately adjacent to the oxygen ports are covered by circumscribed sheets of nickel foil which prevent localized drying of the underlying matrix which would otherwise occur due to the concentration of dry oxygen flowing out of the oxygen ports. The aforesaid structure has been found to have a useful but limited life span due to ultimate clogging of the oxygen ports by a product resulting from corrosion of the fiberglass frame caused by the high purity oxygen, proximity of the KOH electrolyte, and heat generated by operation of the cells. When oxygen port clogging occurs, the cells will fail due to oxygen starvation.